I have been asthmatic my entire life, and I have found sport to stave it off for the most part. It usually bothers me more in colder weather, but I have salbutamol for attacks and Qvar (beclometasone dipropionate) to take tegularly. Not that I do most of the time #livingontheedge

I would recommend the disc version, I have it and the brakes have saved my life multiple times racing down mountains! Not sure what your budget is but I got mine ex display at £1200... had to buy my own racks, bottle cages and a better saddle, but it was worth it to me.